There are 15 words that start with 'extre'.
| extrema | extreme |
| extremer | extremes |
| extremum | extremely |
| extremest | extremism |
| extremist | extremity |
| extremisms | extremists |
| extremeness | extremities |
| extremenesses | |
Note: These 15 words that start with 'extre' are found from the USA & Canada version of the tournament Scrabble word list.